1. Field of the Invention
The invention relates to the field of conveying technology, and in particular to a conveying system, a conveying element and a guide path.
2. Description of Related Art
Conveying systems comprise conveying elements which are conveyed along a conveying path in a manner linked to one another or individually. The conveying elements comprise means for conveying objects as piece goods (and apart from goods, also persons or animals), or as bulk goods. These means can be grippers or other elements, which are designed for holding an object, or can be elements which extend in a planar, two-dimensional manner, on which or in which the objects lay. Such elements extending in a planar, two-dimensional manner are for example conveyor belts, or comprise linked, typically rigid conveying elements which are displaceable with respect to one another, in order to be able to travel through curves. The conveying elements form an essentially flat surface, on which the conveyed product is conveyed. These linked conveying elements for example are known as mat chains, link chains, slat chains, plate chains (flexbelts, chain belts, carrier chains). They are hereinafter collectively called “modular belts”.
Conveying means are mounted differently depending on their type: grippers are mounted for example by way of ball-mounted rollers. Modular belts are for example supported in a planar, two-dimensional manner and thereby slide on slide rails or slide surfaces. Depending on the loading due to the conveyed product, this leads to high friction forces as well as wear, and necessitates corresponding drive forces for moving the modular belt, causing high tensile forces on the modular belt. Other embodiments of modular belts comprise co-running rollers that are part of the modular belt itself, which roll on a surface.
EP 1 070 012 B1 shows chain elements for a modular conveyor belt, without a rolling mounting.
WO 90/02269 shows a rolling element cage with sets of in each case three or also only two bearing balls which roll on one another, wherein each of the bearing balls in turn rolls in a groove on the inner side of a guide rail which partly encompasses the rolling element cage. The rolling element cage is mounted in a linearly displaceable and rotationally fixed manner in the guide rail by way of the mounting in the grooves.
EP 1 009 693 B1 discloses cage-like guide rails with conveying elements rolling therein. In one embodiment, three bearing balls rolling on one another are likewise present, wherein each of the bearing balls in turn rolls on two rods of the guide rail, so that the conveying elements run in a rotationally fixed manner.
U.S. Pat. No. 2,830,824 describes a roller vehicle which can be displaced on a plane surface in all directions and for this is mounted in a rolling manner on several balls, wherein each of these balls in turn rolls on several bearing balls.
CH 663 773 A5 describes a ball joint link-chain which is mounted in a guide rail between two rows of balls which lie opposite one another.
U.S. Pat. No. 2,952,145 discloses a linear ball bearing, in which a hollow body is arranged around a shank and mounted in a manner, in which it is displaceable along the shank and rotationally fixed. Balls are in each case arranged in a paired manner in correspondingly arranged grooves, between the hollow body and the shank, so that the balls on the one hand roll on the hollow body and the shank, and on the other hand on one another.
A spatially movable conveyor is disclosed in DE 37 90 593, with a tension chain of elongate links, in which a bearing ball is arranged, which rolls between four guide rails.